Decoding the Weather Machine

[Len W]

Programme on PBS America (Freeview 94) tonight 7.50 to 9.00 pm.
The first of two parts.
Might be interesting, considering the variables in climate change.

Len
Wembury, SW Devon

[John Hall]

Thanks for the alert. The second part is on at the same time tomorrow - not next week, so don't be caught out.

[quaesoveritas (Whitley Bay)]

Actually each part is on three times, so plenty of opportunity to catch it.

I think that this was originally broadcast (on the BBC?), possibly a couple of years ago and it will therefore be a bit out of date but the date references may be wrong.

The BBC recently broadcast a Horizon called "What's Wrong with Our Weather", which was several years old and was confusing because it kept referring to "last winter" when is wasn't.

It may still be worth watching again, if only for something to complain about. :-)

[Len]

No, this is a UK premiere.

Quite good, once you get past the first 5 mins which is all sound bites and eye candy.

Does a carbon budget and covers a bit of history of the measurements.

The second part is tonight at the same time, so we shall see what conclusions are drawn.

It seems fairly well balanced so far.

Len

Wembury, SW Devon

[John Hall]

Most of it was good, I thought. But I wasn't happy with the suggestion that more extreme weather events were occurring now than in the past, for which no hard evidence was provided. They seemed to largely rely on the subjective opinion of one meteorologist from Minneapolis. It might be true, but it remained no more than an assertion rather than something that the programme set out to prove. Perhaps they will attempt to do so in part two.

[Trevor Harley]

I thought "Orbit", a three-part series recently shown on BBC4 and still available on iPlayer (I think; time flies at my age) was very good EXCEPT for the unnecessary loud music. It explained the Milankovitch cycles very nicely, for example. They too kept talking about "recent very cold winters" and it turned out to have been made in 2011. I wish the schedules told us when programmes were made.

[John Hall]

I think they want us to assume that programmes are new, thinking that that will make us more likely to watch them. For most programmes that doesn't much matter, but for science documentaries it often does. My TV guide indicates when shows are repeats, but unfortunately programmes on BBC 4 that were previously shown on BBC 2 don't seem to be counted as being repeats.

I think I missed Orbit, which is a pity.

[quaesoveritas (Whitley Bay)]

Music on documentaries is a real bugbear of mine and I find it very annoying.

It isn't so much the volume of the music, although that is annoying as much as the way they use different types of music to manipulate the way you think.

Its got to the stage where I don't think people don't realise they are being manipulated, but once you realise it is happening hear it all the time.

Its actually just as important as the commentary, albeit much more subtle.

Earlier documentaries didn't have much music,  and what they did have was appropriate or neutral.

Obviously its the standard way of making documentaries these days.

I wish there was some way of turning it off, without turning off the commentary.

On Wednesday, 3 October 2018 09:13:18 UTC+1, Trevor Harley wrote:

[quaesoveritas (Whitley Bay)]

I was wrong, apparently it is new to PBS UK, although it was broadcast in the US earlier in the year.

I was probably getting it confused with one of the many other documentaries on the subject which have been broadcast.

PBS UK does broadcast a lot of  programmes made by other channels and calls them "premiers",  but that is only on PBS UK..

[Trevor Harley]

ALTHOUGH on the final episode they did say "from the spring equinox the days start getting longer". I think Jack noticed a forecaster saying this some time ago (six months). It must be a fairly common means of mis-explaining things.

[Alastair B. McDonald]

Trevor,

Day can have several meanings. See https://www.thefreedictionary.com/day where it states:

day

(deɪ) n

1. (Horology) Also called: civil day the period of time, the calendar day, of 24 hours' duration reckoned from one midnight to the next

2.

a. the period of light between sunrise and sunset, as distinguished from the night

b. (as modifier): the day shift.

So the Weather machine would have been wrong if they were using definition 1 but not using definition 2a.

[Trevor Harley]

But "the period of light between sunrise and sunset, as distinguished from the night" gets longer from the solstice, not the equinox. They made it very clear they were talking about the equinox.

[Alastair B. McDonald]

Yes they should have said "from the spring equinox the days start getting longer than the nights".

[Len W]

There was not much evidence for increasing occurrence of  extreme events at present given in part 2.

The models seem to indicate it apparently. More cat 4 and 5 hurricanes was quoted.

The graph of calculated global temperature increasing between 1900 and 2000 was shown with model data following the trend.

It obviously was not an exact match, proving models cannot cope with feedbacks. Clouds being one problem which they mentioned to give them credit.

The programme ended quite well with a lot about renewable energy sources.

It's all about money of course.

Businesses will want to make money out of replacing the non- renewables with renewables.

Is there an urgency shown by all countries across the world?

I don't see it.

Len

Wembury

[quaesoveritas (Whitley Bay)]

The graph of past observed global temperatures v the climate model predictions (1900-2000), looked very impressive.

However, the predictions and observatins of the models after the year 2000, were not shown.

The model outputs for prior to 2000 were not forecasts they were hindcasts, done retrospectively.

I do not think that hindcasts are a very reliable way of assessing the future accuracy of climate models.

Obviously, a more reliable approach is to compare accuracy of forecasts since the year 2000, when in fact, the models do not perform very well.

In every year since 2000 the  observed global temperature has been below the multi-model mean forecasted temperature.((average of HADCRUT4/NASA and NOAA) adjusted to 1986-2005)..

In only one year, 2016, has the observed temperature been even close to the model mean forecasted temperature, when the NASA/GISS temperature marginally exceeded the forecasted temperature.

This is based on CMIP5 RCP 4.5, which is actually the second lowest emissions scenario of the IPCC projections, the lowest, and the one which has proven to be the most accurate so far, being the "Commitment" scenario, (RCP 2.6), which is based on ZERO growth in emissions from 2000 onwards. 

Of course not all of the models perform badly and there are about 3 out of 42 which currently are projecting lower temperatures than observations.

Of course, I do not expect those in this group to agree with this, and no doubt I will be accused of being a "global warming denier" again.

Note however, I am NOT saying that the world is not getting warmer, only that it is not warming as fast at the models predict.

I attach a copy of the graph shown in the program, and one of temperatures from 1980 - 2018 (YTD).